Emergency traction device



C. J. GARDETTO EMERGENCY TRACTION DEVICE Sept. 8, 1953 Filed Nov. 17 1949 2 Sheets-Sheet l JNVENTOR. CHHRLES J. GHRDT T0 id, RIVEYS' Sept. 8, 1953 r c. .1. GARDETTO EMERGENQY TRACTION DEVICE Filed NOV. 17, 1949 2 Sheets-Sheet 2 m n mm 3 0 G a Z R m C attorney I supported by Patented Sept. 8, 1953 uNi-TEo?srATEs PATENT, o-FFI 2,651,347 I EMERGENCY TRACTION DEVICE v Charles .r. Gardetto, Cudahy, Wis. Application November 17, 1949, Serial No. 127,828

This invention relate's generallyto improvements in emergencytra'c'tiondevices, and more particularly to a tire chain of a clamp-on type.

Although the invention has particular-utility as applied to automobiles whose wheel rims either are not provided with apertures through which the conventional strap may be inserted, or where such apertures are obstructed by wheel disks or the like, the disclosed clamp constructions have advantages when applied-to any type of automobile wheel.

Heretofore, the-only automobile wheel chains in general use have beeneitherthose which completely encircle the peripheral circumference of the wheel, or those versely around the wheel.

It is the principal object of this invention to employ novel structural means for automatically increasing pressure between the clamp and wheel by utilizing the rotational energy of the wheel itself, the arrangement being such that traction on the chain increases the grip of the clamp upon the rim.

' Other objects will be more apparent from an examination of the following disclosure.

In the drawings:

Fig. 1 is a side elevational view of the emergency chain afiixed to a wheel of an automobile.

Fig. 2 is a perspective view of the emergency chain disassociated from the wheel and showing structural details.

Fig. 3 is a cross sectional view taken along the 'line 33 of Fig. l.

Fig. 4 is a cross sectional view taken along the line 4-4 of Fig. 1.

Fig. 5 is a view in side elevation showing a modified embodiment of the invention applied to a wheel.

Fig. 6 is a view taken in cross section on an enlarged scale.

Fig. 7 is a view in perspective of the modified embodiment of the invention shown inFig. 6.

Fig. 8 is a detail view taken in cross section on the line 88 of Fig. 6.

Conventional automobile wheel construction normally comprises a tire, l mounted upon a wheel rim 1 I, which rim is provided at both outer peripheral edges with outwardly curving flanges 12. Between such flanges, the rim has cylindrical web portions H8 at each side of its drop center i l I. The rim is conventionally centrally a wheel which includes a felloe l3 having spokes it between the felloe and the rim, the spaces between the spokes being designated .as apertures l5. It is through these apertures I that the straps of the conventional mud hook or tire chain are inserted. Even where apertures are available, however, it is not always a convenient matter to apply'a chain strap as this operation requires considerable dexterity in reach-' which are strapped trans- .motorists clothing in the process.

portions 12 of the rim ll.v

is so biased as to exert clamping pressure through arm members It and pads 20against the flanged The pads are desirably made of rubber or likematerial of high frictional coeificient. It is not contemplated that the spring act as a mud hook, that function being performed by a chain 23 to be hereinafter more fully described, but rather as a clamp and as a pivot in connection with the op eration of the chain. The spring, arms, and pads are so dimensioned-as to contract the spring against the tire and the pads against the outer periphery of the rim flange l2-on a diameter of the wheel, this being the shortest distance between the inner and outer circumferences of the tire.

The pads 2c are mounted on relatively rigid backs 2| which are in turn secured to the arms l9through rocking pivots 22 which comprise the ends of the arms IS. The backs 2| and pads 20 are generally arcuately shaped and the pads 20 are rounded in transverse cross section. This shaped construction in connection with the rockable pivot support permits a close frictional fit between the pads and the contours of the flanged portions I2 of the-rim II.

The spring I 8 is so biased as to enable the arms l9 to be conveniently sprung apart when the clamp is placed about the wheel. After positioning on the wheel, the spring bias is such that the clamp is held securely on the wheel with the pads engaged within the rim flanges [2. Such spring bias, however, would be insufiicient to prevent the rotational influence of the wheel on the chain from dislodging the clamp under normal emergency conditions. In order to increase the clamping pressure of the pads against the rim and thus prevent the dislodgment of the clamp during operation, the chain 23 is attached to the clamp at the pad portions thereof and is of such length as to extend along a. chord of the wheel at-right angles to the diameter on which the arms of the clamp are disposed. Thencethe chain passes about the periphery of,

and increases the traction between said tire andthe ground when pinched between the tire and ground as the wheel rotates. I

The attachment of the chain to the pad portions of the clamp and the right angulanchordal alignment assumed thereby when the chain is under tension, results in an increased clamping action of the clamp on the rim. The tension induced in the chain when it is pinched between the wheel and groung will tend to draw the clamp pads along the chord defined'by the chain. However, the snug fit of the clamp about the tire will cause the spring 18 to act as a pivdt about which permitted movement ef the pads would necessarily be defined. Such an arcuate movement of the pads would, however, tend to force the clamp from its major chord spositionto a minor chord position and thus increase the distance between the spring and pads. Since the pads are restrained irom such arcuate move- "rhent by "Contact with the inner faces of flanges 12, "and the distance between the clamp spring "and pads is limited by the physical dimensions "threoffchaintensio'n will serve only to increase the 'fritiohal binding between such pads and the ri'rh fla'n'ge.

The pads are prevented from riding over the flange edges, when under-chain tension, hy-the *inward'biasing influence 'of the spring Hand in addition by 'virtue'of the 'leveredattachment of the chain to the pads. The respective endsof ;;iiai'n -2s are attached to the clamp at the ends 25 of th'e angle levers "or brackets 26 which are ciiri 'iected with the :pads'and iulcrumed at the pivots-=22 The levers *have their resistance ends itbearin'g' againstthe lower portions of the pad backs 21. Although thebrac'kets '26 are shown as separate pieces pivoted -on the arm ends :22, this i is inerely by way of illustration, it 'being immaterial whether"they are separate from the backs-2|. By'means of this novel construction, chain tension is transmitted through the levers in scene manher as -to force the lower portions {of 'the-padsQ-U inwardly and additionally a-into 'fu'rther frictional "contact with the flange portion I 2 6f the" rim.

The emergency cha'in is designed to 'be used only to increase traction whenever the automobile has become immobilized in' heavy-snow ormud *or the like. :It-is not intende'dtobe semi-permanenu 'amxed to' the wheel-as an anti-skid device, but is to-be removed from' the wheel -as "soon as the automobile 'hasregained its mobility. Its removal "isas -siinple as" its application, the

afms-of the spring simply being I sprung apart to 1 free the pads from the rim.

The device shown in -Figs.-5' to 8 uses-a somewhat different principle in i that the cle3niping engagement *is effected thro'u'gh a mechanical lock rather 'than through resume-means. '-T-he= --band- H30 -which' spans thetread surface of tire A it) comprises a*r'elatively rigid strap haiiing one arm- I'BDponti-milng around the 'inner "sidezof the tire casing andponnected -rigidly at with a shoe 210 which 'desirably has a facing 'pacl 2'00.

The-otherarm: 19! on -the outside or the tire casing "is "provided'--vvith a 'r'ig-id permeation at 22 i to a hinge leaf 25 F 'whi ch ear-nesa pintll'l whereby the hinge leaf-2 8 '-is pivoted"td this %nd of the" strap. "Thehinge leaf 28=isrigidly secured,

to the strap-extension" 30; the-inwardly curved end of which-is Secured air-3 l to the shoefl l l avhi'ch,

7T 2 3" iised W'itl'i this 'embb diment bf bhe invention "pears me same relationship ito :itheiitire rrwhich has already fbeen 'described butds-desirablycccnerected rigidly to' the arms 190-: at conesside of fthe device and to the arm extension 3u *at:theother,

4 The arm extension 30 has an end portion 33 which projects outwardly of the tire casing beyond the hinge as is clearly shown in Figs. 6 and 7.. Near its free end, the portion 33 of the 5 extension letter .30 canries a spring .clip 34 normany engaged with the relatively rigid arm portion l9! of the strap I80, such engagement being illustrated in Figs. 6, 7 and 8.

ilEt will he {observed that whereas the pads and shoes 2! of the device illustrated in Figs. 1 to '4 are directed inwardly to face each other .andtaengagethefianges 12 of the rim, the shoes 2H) and 2H and pads 200 of the device shown in to-7 are directed radially outwardly of the wheel and engage the inner peripheries of the cylindrical portions I I9 Let :the .rim, at opposite .ESidlGS :of :its Ail- Q9138 ter H I EDhe :device is readily applied and removed by zpivotally moving :the extension about its piv- 5-20 :otazl connection with the relatively rigid arm [91 ref strap 180. The initial pivotal movement :of ithe extension rflppcsed by the frictional :grasp .0fithe clip :35 upon the arm l-9l. It is rfurthercopposed by -the engagement -of the out- 133 of extension lever 30 with the casing. However, there is enough resil- 'iencie'bothtinitheicasing aminet p to permit -thesshoe2H stozbeziorcedifree of the rim, wherev-.up1onatheeentire devicefrmaiyt-bfi disengaged from about the :tire teasing.

The application of theaiev-ice-gto the-tirecasing isithezreverseof that described. The fixe D tions ucf --strap 1:80 amd rarm lgal) :are engaged :aroundsthe'zrearisiiieacf:the casing with pad 2E0 :in-contact-mithaportion :llnrofthe rim at the iinnersi'deiofithe wheel. .ThiS llS'TBEtdilY accompli'she'dlwn-thithesstrap extension :39; angularly displaced several degrees clockwise from the position illustratediinrfligr6. Withwthe-strap i8 9 in 40 a position-where itiis'about-to engagethe tread portion of the casing, the straptis xirawninwardly "upon the casingwhilezatthe same .time,athe shoe 2H aind 'itsapad Z'Ilflzarerforccd within the cylinedrical porti'on :of the rim :;-atthe outside of the tavhe'el. A's these partsimeverinto position, the

extension lever 30 swings towardaparallelism with arm tiil as illustratediiiniFigsmfi-and :7 and ultimately the clip 35 engages arms.:l.9l .to-maintain the parts ein clamping engagement with 1 the wheel rim with its tire casing.

in the dev-ice i-previously described, the "chain 23 lags behind theYtiresenga-gi-ng @strap to the extent indicated in Fig. 5, being.-..of=.such-;a *i'er i'gth asdes'ira'biy :(though .not necessarily) to be approximately at right angles to the diameter or -the wheel upon-whi'ch the-strap is disposed. "The retative 'thrust exerted by the tire casing upon the *ro'ad,=- and-upon that; portion of the chain 23 which intervenes-betweenthe tire caslvided which may;ibe'iclamped on to thesrim of Ian automobileawheel, and which; include chains =.of:.-ssuch easlengtmxandssecured. to ,the clamp in such: asfashionieasto .utilizethe rotational energy not :the wheel-to :increaserthe binding pressure be- 1-15.:tweenrthezclamprandlthfi rimiso as'toprevent the clamp from becoming dislodged during operation.

I claim:

1. In a traction device of the character described for engagement with an automobile wheel having a rim, a tire encircling clamp having spaced arms, rim engaging shoes connected to the free ends of said arms for contact with said rim, and a tire-encircling chain havin its ends connected with said arms, the portion of the chain intermediate such connections being free and of greater length than required for direct tire oncirclement whereby to encircle the tire at a point peripherally spaced from said clamp, the connections of the chain to the arms comprising lever means responsive to chain tension to frictionally bind said shoes against the rim.

2. The device of claim 1 wherein the connection between the rim engaging shoes and the arm members comprises a bell crank provided with a pivotal connection with the free end of each arm for oscillation on an axis generally longitudinal respecting the arm, the bell crank having outwardly projectin levers to which the chain is attached.

3. The device of claim 1 wherein the shoes comprise pads arcuately shaped to conform substantially to the contours of the wheel rim flanges.

i. The device of claim 1 wherein the shoes have connections to the free ends of the arms which are rigid against displacement under the tension of said chain.

5. In a traction device of the character described, the combination with a tire encircling clamp comprising a tread engageable strap por-- tion and spaced inwardly extending arms, of rim engageable shoes connected to the inner end of the arms, and a tire encircling chain of materially greater extent than the combined length of said strap and arms, said chain having its ends connected with said clamp adjacent the inner ends of said arms and having a loop portion entirely free intermediate such ends, the connection of said chain with said arms comprising lever means responsive to chain tension to frictionally bind said shoes against said rim.

6. The device of claim 5 in which the ends of the chain are connected with said arms outwardly of said shoes.

7. The device of claim 6 in which one of said arms has a hingedly movable terminal portion carrying its respective pad and to which the chain is connected.

8. The device of claim 7 movable portion comprises a lever having a pintle connecting it intermediate its ends to one of said arms, one end of said lever carrying the respective shoe and the other end extending outwardly along the tire-proximate side of the arm with which the lever is hingedly connected and provided with a clip in detachable engagement with said last mentioned arm.

9. A traction device of the character described for engagement with an automobile wheel rim and tire casing, said device comprising the combination of a tire encircling clamp having a tread engageable strap, a first arm extending inwardly across the tire and provided with an end oiTset for disposition within the inner periphery of a rim and provided with an outwardly facing rim engageable shoe having an arcuate surface, a second arm extending inwardly to lie in proximity to the other side Wall of a tire and terminating short of said rim, and an arm exin which the hingedly tension lever in hinged connection with the terminus of said last mentioned arm and provided with a terminal ofiset provided with an arcuately surfaced shoe for inner peripheral engagement with said rim, detent means for securing said extension to said arm against hinged movement from a position in which its shoe is in rim engagement, said arm and extension having overlapping portions engaged by said detent.

10. The device of claim 9 in further combination with a chain having a slack intermediate portion of greater length than the combined length of said strap and arms and extension, said chain having its ends respectively connected with the first mentioned arm and with the extension of the arm second mentioned.

11. The device of claim 10 in which the said extension comprises a lever extending outwardly beyond its hinged connection with the second mentioned arm along the tire-proximate side of said arm, the said detent means comprising a. spring clip carried by the outer end of the lever in a position for releasable engagement with an intermediate portion of the second mentioned arm.

12. In a device of the character described, an automobile wheel-rim-engaging clamp comprising a spring member, arm members fixed at each end of said spring member and which partially encircle a tire mounted on said automobile wheel said spring, said pads being arcuately shaped and or rounded cross section for engageable contact with the automobile rim, said spring being so tion faces and said offset clamp portions com- 1loirise brackets extending outwardly from said CHARLES J. GARDET'IO. References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,255,534 Hons Feb. 5, 1918 1,537,862 Mohr May 12, 1925 1,994,065 Dean Mar. 12, 1935 2,440,863 Liggio May 4, 1948 2,457,208 Carpenter Dec. 28, 1948 

